Upper Diamond Lake in Boulder County: How and When to Fish It

• Overview

  You will find Upper Diamond Lake in Boulder County, Colorado. It stands 11,726 feet above sea level. The water measures roughly 5 acres, so nothing here is far from anything else. On size it sits at the modest end of our Boulder County list. Fraser lies 8.3 miles from the water. Nederland is 8.8 miles away, with Granby at 16 miles. It sits near the edge of the county, so check which rules apply.

• Where to Fish on Upper Diamond Lake

  Depth remains unrecorded, so treat the first session as a survey. The productive water is a rod length or two out, not a hundred. Still water like this holds fish on the edges rather than out in the open. Reported across Boulder County: black-spotted cutthroat trout, brook trout and brown trout. The county list is broader than any single water. Take Upper Diamond Lake a stretch at a time.

• Seasonal Patterns

  Seasonal averages run from 18°F in January up to 53°F in July. Seasons are distinct, and each one fishes differently. The open season starts with the thaw, near enough mid May. On average, mid May opens the water and mid November closes it again. From the thaw to midsummer the fishing improves week by week. Keep it in mind when planning a trip to Upper Diamond Lake.

• Tackle & Baits

  Our records carry no access rule either way. No car park, ramp or path is recorded within easy reach of the shore. Light line and small metal for the trout; a fly rod earns its place on calm evenings. Rules for this water may differ from the county norm. Rules for boats are stricter than rules for the bank in many places. Upper Storm Lake sits 0.6 miles off and takes the overflow. For Upper Diamond Lake, the notice at the access point is the final word.